n = int(input())
prices = list(map(int, input().split()))
dif = []
for index in range(len(prices)-1):
dif.append(abs(prices[index + 1] - prices[index]))
print(max(dif))
n = int(input())
prices = list(map(int, input().split()))
dif = []
for index in range(len(prices)-1):
dif.append(abs(prices[index + 1] - prices[index]))
print(max(dif))